1.Thanks for Device Manager . I would not have guessed so myself about it

2. So. What is changed? Now we need have another hardware to use 'arm-emulators' (non x86) ?

But Release Tizen Studio 2.0:

Emulator To use the Tizen emulator, install an Intel VTx supported by the CPU, and the latest version of the graphic card driver provided by the vendor. Check the prerequisites for the Tizen emulator from Prerequisites for the Tizen Studio.

So What do you ( Tizen ) change with Emulators? I can use all divices emulators on old SDK 2.3.1, but after Tizen update or Win10 update I can use only 3.0

If that's the case, From my end I would suggest to deploy apps on '2.3.2 emulator'. '2.3.2 Emulator' is 'Tizen 2.3.1 application' compatible. I mean, whatever '2.3.2 Emulator' is responding you can expect more or less same behaviour from '2.3.1 Emulator'.